1. Field of the Invention
The present invention relates to a method for producing seasoning liquids, more specifically to a method for readily producing seasoning liquids having a high nitrogen content in a short period of time by using vital gluten which is hardly used as a raw material of seasoning liquids.
2. Description of Related Art
Soy sauce has now been used as a world-wide seasoning not only in home cooking but also in a variety of processed foods.
In general, soy sauce is produced by inoculating seed mould in a mixture of cooked soy bean and roasted wheat, culturing the mixture to make a soy sauce koji, which is prepared together with brine in a brewing vessel, fermented and matured for a long period of 6-12 months. In the process of fermentation and maturation, the mixture is hydrolyzed with the enzymes of koji into flavor enhancing ingredients or by lacto-bacillus or yeast into organic acids such as lactic acid, various alcohols such as ethanol, and a variety of flavors, thus producing a seasoning having characteristic taste and flavor.
On the other hand, there is a method for using wheat gluten in addition to soy bean as the protein materials for preparing high nitrogen containing soy sauce or soy sauce-like seasonings.
Wheat gluten is prepared by kneading wheat powder in water to give a sticky lump, to which is added water for further kneading to rinse off soluble components such as starch.
Wheat glutens are largely classified into vital glutens such as a gluten which is a water-containing wheat protein obtained as described above (referred to hereinafter as hydrous vital gluten) and a vital gluten which is the hydrous vital gluten having been dried while avoiding the denaturation of the protein (referred to hereinafter as dry vital gluten), and devitalized glutens which are the wheat proteins obtained from the aforementioned hydrous vital gluten by denaturation treatments with heat or acid (referred to hereinafter as devitalized gluten).
While the hydrous vital gluten containing a large amount of water is deteriorated very easily and thus commercially distributed at a low temperature or in a frozen state, the dry vital gluten is in a dry powdery form and hardly deteriorated, so that they have an advantage that they can be easily stored or distributed commercially.
The dry vital gluten has a reversible physical property, which will be returned to the original physical property, that is the sticky gum form, by the addition of water. On the other hand, the devitalized gluten which is the denatured wheat protein has an irreversible physical property and is not returned to its sticky gum state even by the addition of water, so that it is easily handled on adding to food materials, but it is expensive relative to the dry vital gluten.
Among the wheat glutens, the vital gluten is used mainly for the production of processed foods such as meat products, breads and noodles, while the devitalized gluten is used as a raw material of soy sauce, amino acids and animal feeds.
The dry vital gluten has a reversible physical property as described above on its use as a raw material for foods blended with liquids and results in the increased stickiness, which causes problems inconvenient to its dispersibility, solubility, pressing ability or total nitrogen utility, so that it has hitherto been extremely difficult to use the dry vital gluten as a raw material of soy sauce or seasoning liquids. That is to say, when soy sauce koji and powdery dry vital gluten are blended with brine to make dispersion of moromi mash having the brine absorbed therein, the dry vital gluten is hardly dispersed and results in a number of spherical lumps. The lumps contain brine which is absorbed only in the surface, and form sticky gum film on the surface, so that the brine does not penetrate into the interior, which remains in the powdery form. In addition, if such lumps have been formed, it is extremely difficult to destroy the lumps with any means for blending and agitation, so that the lumps remain as such even after maturation period. The occurrence of such lumps inhibits the permeation of enzymes contained in koji, and thus the raw materials in the lump part are scarcely hydrolyzed. As a result, the ratio of the nitrogen utilized as soy sauce or seasoning to the nitrogen contained in the raw materials used (referred to hereinafter as raw material nitrogen utility) is lowered extensively. In addition, the pressing ability is also decreased extensively, the yield of soy sauce or seasoning is poor. The part of lumps into which brine is permeated only insufficiently is susceptible to the contamination by microorganisms and thus may cause inconveniences such as abnormal fermentation.
Because of such inconveniences owing to the use of vital gluten, the devitalized gluten which is a denatured wheat protein having an irreversible physical property and being easily blended and dispersed is currently employed as the gluten used as a raw material of soy sauce or seasoning liquids.
The present invention has been done for the purpose of solving the aforementioned defects in the conventional method for producing a seasoning liquid by blending and dispersing soy sauce koji and the vital gluten into brine, and providing a process for obtaining with ease a high nitrogen containing seasoning liquid excellent in total nitrogen utility within a short time by blending the vital gluten with soy sauce koji and brine and thus resulting in a dispersion.